Flame arrester for carburetors



July 4, 1933.

L. W. WILLIAMS FLAME ARRESTER FOR CARBURETORS Filed April 9, 1930INVENTOR BY W 1&4

ATTORNE 5 Patented July 4, 1933 UNITED STATES PATENT OFFICE h LEWIS W.WILLIAMS, MORRIS TOWLISHIP, MORRIS COUNTY, NEW JERSEY, ASSIGNOR TO MOTORIMPROVEMENTS, INC., OF NEWARK, NEW JERSEY, A CORPORATION OF DELAWARE vFLAME ARRESTER FOR CARBURETORS I Application filedApril 9, 1930.- SerialNo. 442,770.

This invention relates to a'flame arrester for the carburetor of aninternal combustion engine for preventing explosions or fires from theback-firing of the engine and has as. an

object a simple, eflicient and economical flame arrester for preventingsuch occurrences.

A device embodying'this invention comprises a metallic filter arrangedat the mouth ofthe carburetor or intake. This filter 1s provided with anarrow inlet of suflicient total'area to permit flow to theintake oftherequired amount of air for proper operation of the engine. However, theinlet is sufflciently narrow that in the event of backfiring of theengine, the flame 1s IQiiLlIlGCl within the filter and is thus preventedfrom being communicated to the surrounding atmosphere. Thus, althoughthe engine may be surrounded by combustible fumes, the

possibility of an explosion or conflagration is effectively prevented. I

Other objects, novel features and advantages of this invention will beapparent from the following specification and accompanying drawing,wherein:

Fig. 1 is aside elevatlon of an internal combustion engine, thecarburetor of which is provided with a flame arrester embodying theinvention.

Fig. 2 is a side'elevation of the flame arrester.

Fig. 3 is an enlarged fragmentary section on the line 33 of Fig. 2, and

Fig. 4 is a perspective view'of a portion of the device. I

In Fig. 1, 10 represents a conventional in ternal combustion engineprovided with a carburetor 11 having an air intake pipe 12, at the mouthof which is arranged the flame arrester 13. The flame arrester comprisesa hollow substantially cylindrical casing 14. The upper end of thecasing terminates in an -inwardly projecting neck 15 and the lower gine.:The flame arrester is thus supported by the intake pipe and thebracket.

The casing 14: is provided with a pair of' peripheral ridges 18 and '19and between these ridges the casing 14 is longitudinally fluted as at20. In the grooves formed by bon 22 which is preferably preformed sothat it naturally assumes helical shape. At regu larintervalsprojections 23 extend from one face of the ribbon and provide means forspacing apart the adjacent turns. These projections are very minute sothat the space between adjacent turns is very narrow. .The projections23 form alarge number of narrow slots which constitute the air intake.The ribbon 22 is several times as wide as it is thick, but due to thepreforming of the ribbon with suitable curvature, the turns lie evenlyand are uniformly spaced.

The total inlet area formed by the spacing of the turns of the helix issutficient to allow the flow of the required amount of air for properoperation of the engine with which the device is used. However, thewidth of the inlet slot is so restricted as to prevent the passage offlames therethrough. The width of the slot may be of the order of1/1000ths'of an inch, but may be varied as conditions justify. Also, thewidth and thickness of the ribbon may be varied to meet differentconditions.

- The normal operation of an engine is not affected by the use of theflame arrester above described. Air passes through the inlet slotprovided in the helix and through apertures 21 into the interior of thecontainer from whence it flows through the intake 12 into the carburetor11 where it is mixed with gasoline in the well-known manner to form afuel mixture for Y the engine. The device also serves to filter out fromthe air solid particles which otherwise would be taken into the carburetor. In the event of the engine back-firing, the flame is confinedwithin the casing 14 and is effectively prevented from beingcommunicated to any combustible fumes that might be in the vicinity ofthe engine and the possibility of explosion from conflagration due tothe back-firing of the engine is thus effectively eliminated. a

It is of course understood that various modifications may be made in thedevice above described without in any waydeparting from the spirit ofthe invention as defined in the appended claims.

I claim: i 1. In combination with the carburetor of an internalcombustion engine, a tubular member-composed oi a helically wound ribbon having projections spacing apart successive turns, the passages thusprovided being sufiiciently restricted to prevent the passage of flamethcrethrough, a fluted hollow member enclosed by and supporting saidmember and forming channels therewith, said supportin member havingapertures es tablishing communication betweenchannels and theinteriorofthe supporting member, and a conduit leading from the interioroi the supporting member tothe car-. buretor.

2. In combination with the carburetor of an internal combustion engine,a tubular member composed of a ribbon wound helically with its widefaces normal to the axis, means spacing the turns of said helix to pro-'vide narrow slots which will pass air and prevent passage of flame, afluted hollow member surrounded by said tubular member and formingchannels therewith, said hollow said.

and endmembe-rsfor said tubular member,

one of said end members being adapted for attachment to the air intakepipe of the carburetor. i v

4:. A flame arrester fornse with the carburetor of an internalcombustion engine comprising a tubularmember composed of a metal ribbonwound helically with its-wide faces normal to the axis of thehelix andhaving ,pl0]6Ct-1OI1S spaclng apart the successive turns, the passagesthus provided being sufli.

ciently restricted to prevent the passageof flame theret-hrough; ahollow memberenclosed by and supporting the helix, and apertures in saidsupporting member establishing communicationbetween said passagesand theinterior of thesupporting member, said supporting member havingprovision for attach ment to the air intake pipe of the carburetor;

In testimony whereof, I have signed my name to this specification.

LEWIS \Y. WILLIAMS.

